Moses the First Prophet

Then Moses answered, "What if they won't believe me and will not obey me but say, 'The Lord did not appear to you'?"
The Lord asked him, "What is that in your hand?"
"A staff," he replied.
Then He said, "Throw it on the ground." He threw it on the ground, and it became a snake. Moses ran from it, but the Lord told him, "Stretch out your hand and grab it by the tail." So he stretched out his hand and caught it, and it became a staff in his hand. "This will take place," He continued, "so they will believe that Yahweh, the God of their fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has appeared to you."
In addition the Lord said to him, "Put your hand inside your cloak." So he put his hand inside his cloak, and when he took it out, his hand was diseased, white as snow. Then He said, "Put your hand back inside your cloak." He put his hand back inside his cloak, and when he took it out, it had again become like the rest of his skin. "If they will not believe you and will not respond to the evidence of the first sign, they may believe the evidence of the second sign. And if they don't believe even these two signs or listen to what you say, take some water from the Nile and pour it on the dry ground. The water you take from the Nile will become blood on the ground." (Exodus 4:1-9 HCSB)

Moses told Aaron everything the Lord had sent him to say, and about all the signs He had commanded him to do. Then Moses and Aaron went and assembled all the elders of the Israelites. Aaron repeated everything the Lord had said to Moses and performed the signs before the people. The people believed, and when they heard that the Lord had paid attention to them and that He had seen their misery, they bowed down and worshiped. (Exodus 4:28-31 HCSB)

Moses was established as prophet publicly by miracles. Moses asked God to prove to the Israelites that He had sent him. Go gave Moses three signs which Moses performed publicly before the Israelites to establish his credentials. After all, he is the first prophet and thus he laid the foundation for the rest of the prophets to follow.

God further confirmed Moses as His prophet with more public miracles:
1. The ten plagues of Egypt (Exodus 8,9,10,11)
2. The pillar of cloud and fire (Exodus 13:21)
3. The parting of the Red Sea (Exodus 14:21-22)
4. The giving of the Law at Mount Sinai (Exodus 24)
5. The daily manna (Exodus 16:35)
6. Water from rock (Exodus 17:5-7, Numbers 20:10-11)

All these were done publicly, in the presence of Israelites and Egyptians.

Moses also established the criteria for true prophets.

"If a prophet or someone who has dreams arises among you and proclaims a sign or wonder to you, and that sign or wonder he has promised you comes about, but he says, 'Let us follow other gods,' which you have not known, 'and let us worship them,' do not listen to that prophet's words or to that dreamer. For the Lord your God is testing you to know whether you love the Lord your God with all your heart and all your soul. You must follow the Lord your God and fear Him. You must keep His commands and listen to His voice; you must worship Him and remain faithful to Him. That prophet or dreamer must be put to death, because he has urged rebellion against the Lord your God who brought you out of the land of Egypt and redeemed you from the place of slavery, to turn you from the way the Lord your God has commanded you to walk. You must purge the evil from you. (Deuteronomy 13:1-3 HCSB)

"The Lord your God will raise up for you a prophet like me from among your own brothers. You must listen to him. This is what you requested from the Lord your God at Horeb on the day of the assembly when you said, 'Let us not continue to hear the voice of the Lord our God or see this great fire any longer, so that we will not die!' Then the Lord said to me, 'They have spoken well. I will raise up for them a prophet like you from among their brothers. I will put My words in his mouth, and he will tell them everything I command him. I will hold accountable whoever does not listen to My words that he speaks in My name. But the prophet who dares to speak a message in My name that I have not commanded him to speak, or who speaks in the name of other gods—that prophet must die.' You may say to yourself, 'How can we recognize a message the Lord has not spoken?' When a prophet speaks in the Lord’s name, and the message does not come true or is not fulfilled, that is a message the Lord has not spoken. The prophet has spoken it presumptuously. Do not be afraid of him. (Deuteronomy 18:15-22 HCSB)

He said,
"Hear now My words:
If there is a prophet among you,
I, the Lord, shall make Myself known to him in a vision.
I shall speak with him in a dream.
"Not so, with My servant Moses,
He is faithful in all My household;
With him I speak mouth to mouth,
Even openly, and not in dark sayings,
And he beholds bthe form of the Lord.
Why then were you not afraid
To speak against My servant, against Moses?" (Numbers 12:6–8 NASB)

Since that time no prophet has risen in Israel like Moses, whom the Lord knew face to face, for all the signs and wonders which the Lord sent him to perform in the land of Egypt against Pharaoh, all his servants, and all his land, and for all the mighty power and for all the great terror which Moses performed in the sight of all Israel. (Deuteronomy 34:10-12 NASB)